Results 81 to 90 of about 407 (175)
General birationality and hyperelliptic theta divisors
Annali di Matematica Pura ed Applicata (1923 -)Abstract We first state a condition ensuring that having a birational map onto the image is an open property for families of irreducible normal non uniruled varieties. We give then some criteria to ensure general birationality for a family of rational maps, via specializations.
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Inverse images of theta divisors
Illinois Journal of Mathematics, 1985 In this paper the author explains a method for computing the linear equivalence class of the inverse image of the theta divisor via a morphism. Then he gives some illustrations of the method. The first part is the explanation of definitions. Three theorems are established. The last part consists of examples.
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On the base locus of the generalized theta divisor [PDF]
Comptes Rendus de l'Académie des Sciences - Series I - Mathematics, 1999 We present a new class of examples of base points for the generalized theta divisor on the moduli space of semistable vector bundles of trivial determinant on a compact Riemann surface and we prove that for sufficiently large rank the base locus is positive dimensional.
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Rank four vector bundles without theta divisor over a curve of genus two
, 2008 8 pagesWe show that the locus of stable rank four vector bundles without theta divisor over a smooth projective curve of genus two is in canonical bijection with the set of theta-characteristics.
Pauly, Christian
core
A scalar Riemann-Hilbert problem on the torus: applications to the KdV equation. [PDF]
Anal Math Phys, 2022 Piorkowski M, Teschl G.
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Structure and magnetic properties of bulk and thin film nickel manganite (NiMn(_2)O(_4)) [PDF]
, 2003 The structural and magnetic properties of nickel manganite (NiMn(_2)O(_4)) have been investigated, for bulk, and thin film samples. NiMn(_2)O(_4) has partially inverted spinel structure, Mn(_v)Ni(_1-v)[Ni(_v)Mn(_2-v]O(_4), where v is the inversion ...
Ashcroft, Gwynfor Rhys
core
, 2004 We construct natural maps (the Klein and Wirtinger maps) from moduli spaces of semistable vector bundles over an algebraic curve X to affine spaces, as quotients of the nonabelian theta linear series.
Ben-Zvi, David, Biswas, Indranil
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On Viazovska's modular form inequalities. [PDF]
Proc Natl Acad Sci U S A, 2023 Romik D.
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The Singular Locus of the Theta Divisor and Quadrics through a Canonical Curve
, 2007 A section K on a genus g canonical curve C is identified as the key tool to prove new results on the geometry of the singular locus Theta_s of the theta divisor.
VOLPATO, ROBERTO, MATONE, MARCO
core
Jacobians with a vanishing theta-null in genus 4
, 2008 In this paper we prove a conjecture of Hershel Farkas [11] that if a 4-dimensional principally polarized abelian variety has a vanishing theta-null, and the Hessian of the theta function at the corresponding 2-torsion point is degenerate, the abelian ...
Samuel Grushevsky +1 more
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